Thermographic properties of a Eu3+-doped (Y0.75Gd0.25)(2)O-3 nanophosphor under UV and x-ray excitation

Abstract

Phosphors are thermographic if their emission characteristics change with temperature. In this paper, we investigated the potential use of a europium-doped (1, 3 and 6 at.% Eu3+) yttrium-gadolinium oxide (Y0.75Gd0.25)(2)O-3 nanostructured matrix for phosphor thermometry and thermometry in high-energy radiation fields. Photoluminescence emission measurements were recorded in the temperature range from room temperature to 873 K, observing temperature changes in trivalent europium ion transitions from D-5(1) and D-5(0) energy levels. The results show that Eu3+-doped (Y0.75Gd0.25)(2)O-3 is a new promising high-temperature thermometric phosphor with a very good sensitivity of approximately 4.9x10(-3) K-1 at 823 K for a sample doped with 1 at.% Eu3+. It is shown that with this material the fluorescence intensity ratio method can be used for temperature measurements in high-energy radiation fields without the use of an optical excitation source. In this case a maximal sensitivity of 2.35x10(-3) K-1 is obtained.